The present disclosure relates to methods and systems for generating heat and/or nitrogen gas in subterranean operations, pipelines, and other related operations.
Crude oil produced from subterranean formations typically contains many kinds of hydrocarbons, including paraffin wax. Paraffin wax is typically dissolved crude oil at higher temperatures and/or pressures. However, paraffin wax tends to precipitate from crude oil in waxy solid deposits when the pressure and temperature is lowered as the hydrocarbon is produced and as the crude oil cools down. Paraffin wax deposition in well bores, tubing, and/or pipelines may obstruct the flow of oil and/or other fluids, lowering oil production and interfering with transportation. Asphaltenes are also a problem in crude oil production in many areas around the world. Asphaltenes may precipitate as solids in the matrix of the formation, in a previously-created fracture in the formation, in the wellbore, or in production tubing. Asphaltenes that precipitate in the formation at lower temperatures can result in plugging of the pores in the matrix of the subterranean formation.
Certain subterranean operations often involve the use of chemical additives and systems such as viscosifying agents, breakers, resins, crosslinking agents, and the like. In many instances, these additives may be more effective or less effective at certain temperatures. For example, certain chemical breakers may not effectively reduce the viscosity of fluids at temperatures below about 200° F., and certain types of crosslinking agents and breakers may be activated only at certain temperatures. Moreover, many encapsulated breakers, crosslinking agents, and other additives may not diffuse out of their encapsulants effectively at lower temperatures. Finally, certain resins may at least partially cure at certain temperatures in a formation, increasing their viscosity and making them increasingly difficult to pump down a well bore. In many subterranean operations, it is often desirable to delay the activity of many of these chemical additives until they reach a selected location downhole. However, temperature conditions in various portions of a subterranean formation may or may not provide effective conditions for activating or delaying these additives.
While embodiments of this disclosure have been depicted and described and are defined by reference to example embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.